path: root/security/integrity
diff options
authorDmitry Kasatkin <d.kasatkin@samsung.com>2014-11-20 16:31:01 +0200
committerMimi Zohar <zohar@linux.vnet.ibm.com>2015-05-21 13:28:47 -0400
commit7c51bb00c40e5608fb2cdac5230f51aeb56a28df (patch)
treeea228d622a60f43812b50ce7e27b2abbb466f04b /security/integrity
parentevm: labeling pseudo filesystems exception (diff)
evm: fix potential race when removing xattrs
EVM needs to be atomically updated when removing xattrs. Otherwise concurrent EVM verification may fail in between. This patch fixes by moving i_mutex unlocking after calling EVM hook. fsnotify_xattr() is also now called while locked the same way as it is done in __vfs_setxattr_noperm. Changelog: - remove unused 'inode' variable. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Diffstat (limited to 'security/integrity')
1 files changed, 3 insertions, 4 deletions
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index 582091498819..1334e02ae8f4 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -387,17 +387,16 @@ void evm_inode_post_setxattr(struct dentry *dentry, const char *xattr_name,
* @xattr_name: pointer to the affected extended attribute name
* Update the HMAC stored in 'security.evm' to reflect removal of the xattr.
+ *
+ * No need to take the i_mutex lock here, as this function is called from
+ * vfs_removexattr() which takes the i_mutex.
void evm_inode_post_removexattr(struct dentry *dentry, const char *xattr_name)
- struct inode *inode = d_backing_inode(dentry);
if (!evm_initialized || !evm_protected_xattr(xattr_name))
- mutex_lock(&inode->i_mutex);
evm_update_evmxattr(dentry, xattr_name, NULL, 0);
- mutex_unlock(&inode->i_mutex);